#include<bits/stdc++.h>
using namespace std;
int main(){
	int n;
	while(cin>>n){
		int mul = 1;// 初值容易出错
		int acc = 1;
		for(int i=1;i<=n;i++){
			cin >> acc;
			if(acc % 2){
				mul *= acc; 
			}
		}
		cout << mul <<endl;
	}
	return 0;
}
